Fordnatics List Archive

This read-only message was archived from a public mail list.
Mail From: (email redacted)

Hi, I am wondering if anyone can help. I have a 93 Cobra and recently
installed 3.55's. Having no luck with the 23 tooth speedo gear, I ordered a
7 tooth drive gear.

I have been to two places trying to get the 7 tooth put in and the first
simply bailed and referred me to a tranny shop. Today, the tranny shop -
which closes at 12n - said it would require complete removal of the tranny,
as removing the "tailshaft housing" - if you can call it that would upset the
shifter-rod detent-balls. They didn't have time to do that today. And $175.
This gear is starting to get really expensive!

I thought I had seen info here stating that this was a possible driveway job
if you had the time. I will be on vacation with the parents next week, which
means I will have access to spare cars and a pretty good garage, including
air tools.

So I am thinking of doing it myself. My question is, how much trouble will
it be and do I really have to pull the tranny. It doesn't look like "all
that much more trouble" to pull the whole thing from what they did anyway -
drop exh, remove shifter, driveshaft, tranny mount and such. Not much else
but unbolting the thing.

(and then pressing the clutch while the input shaft is no longer in place -
<g>

Thanks in advance for your replies.

Allen Frazier
Nashville, TN

This read-only message was archived from a public mail list.
Mail From: (email redacted) (Greg Powers)

> Hi, I am wondering if anyone can help. I have a 93 Cobra and recently
> installed 3.55's. Having no luck with the 23 tooth speedo gear, I ordered a
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
No amount of luck would help you here. Those things just don't work and
are, at best, a temporary solution to correcting your speedo error. Anyone
out there who doubts this should put in a 23 tooth gear, drive about 20 miles,
and then check it. I guarantee that more than half of the teeth will already
be cracked. I've even recieved mail from a couple of people who've had these
gears bind up resulting in a broken drive gear. However, vendors are still
selling these things like candy and many will NOT warn you of these problems.

> So I am thinking of doing it myself. My question is, how much trouble will
> it be and do I really have to pull the tranny. It doesn't look like "all

The guy who replaced my T-5 drive gear said it was just as easy to drop the
whole thing and put it on a bench. His total labor time was somewhere between
3-4 hours at a total cost of $150. Not cheap, but doing something THE RIGHT
WAY often requires a few more $$$. Keep in mind that this was a pro using a
lift and air tools. That equates to an entire weekend of agony on a cold
garage floor for me, so I let him do it.


Greg Powers
((email redacted))

This read-only message was archived from a public mail list.
Mail From: Chris Behier <(email redacted)>

I couldn't agree more with Greg on this. When doing rear gears on a
1990 or newer car (8T drive gear) - one should plan for the swapping
out of the drive gear to a 7T drive gear and matching driven gear.
Actually, hopefully this should be made part of a FAQ of gear
swapping.

I am not sure why FORD decided to do this absolutely *&^%$# in the butt
change on T5's but its sure makes the rear end gear swap more painful
and more expensive. I know - Ford wanted to get rid of 8T gears and 7T
gears so they put the 8T on the T5 expecting all the Mustang perfomance
addicts to empty out their stock

Oh well...

Chris...
(got his 7T in his T5


From: (email redacted) (Greg Powers)
Subject: Re: 93 Cobra speedo gears -revisited
To: (email redacted)

> Hi, I am wondering if anyone can help. I have a 93 Cobra and recently
> installed 3.55's. Having no luck with the 23 tooth speedo gear, I ordered a
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
No amount of luck would help you here. Those things just don't work and
are, at best, a temporary solution to correcting your speedo error. Anyone
out there who doubts this should put in a 23 tooth gear, drive about 20 miles,
and then check it. I guarantee that more than half of the teeth will already
be cracked. I've even recieved mail from a couple of people who've had these
gears bind up resulting in a broken drive gear. However, vendors are still
selling these things like candy and many will NOT warn you of these problems.

[stuff deleted about the cost being about 150 $$$ to get a 7T gear in the T5]

This read-only message was archived from a public mail list.
Mail From: Kelly Murray <(email redacted)>


With all the problems/expense with the speedo-gear, I wonder
if it might be a good idea to have a simple external gear setup
that goes between the speedo and the trans.
Then one could easily just swap gears in that box to calibrate
the speedo correctly. This would make it easy to adjust to
different tire sizes too, not just different rear-end gears.

Seems it wouldn't be too difficult or expensive to make such a box,
and it sounds like there's a market for it.
We must have some enterprising mechanical engineers out there..

-Kelly Murray (email redacted)

This read-only message was archived from a public mail list.
Mail From: (email redacted) (James Dingell)

Mike at Diversified Products has some Mustang speedo reducer boxes and
cables left in stock. He is low on 3.55 rear axle ratio speedo cable
assemblies but has a few extra 3.73 and 4.10 assemblies, too. These
have proven to be the only permanent/responsible way to go over the
long run for us. Plan on spending around $100.00 per assembly plus
UPS. Call Mike at (313) 459-0130. Jim D., PPI


______________________________ Reply Separator _________________________________
Subject: Re: 93 Cobra speedo gears -revisited
Author: Kelly Murray <(email redacted)> at postmaster2
Date: 12/19/94 2:15 PM


With all the problems/expense with the speedo-gear, I wonder
if it might be a good idea to have a simple external gear setup
that goes between the speedo and the trans.
Then one could easily just swap gears in that box to calibrate
the speedo correctly. This would make it easy to adjust to
different tire sizes too, not just different rear-end gears.

Seems it wouldn't be too difficult or expensive to make such a box,
and it sounds like there's a market for it.
We must have some enterprising mechanical engineers out there..

-Kelly Murray (email redacted)

This read-only message was archived from a public mail list.
Mail From: (email redacted) (Greg Powers)

> With all the problems/expense with the speedo-gear, I wonder
> if it might be a good idea to have a simple external gear setup
> that goes between the speedo and the trans.

This can be done by most competent speedometer shops. The cost around
here runs about $100-$125. The original owner of my '90 LX had one of
these reducer boxes put in when he installed 3.55s. Unfortunately, the
thing broke after 10K miles. If you're going to spend that kind of
money for a reducer, you might as well swap out the drive gear.

I know of at least one vendor who carries custom speedometer cables and
reducer boxes, but he told me he doesn't sell very many. Why would you
pay $100+ for a permanent fix when you can throw a $12 gear in once a
year? So what if the teeth on the gear break off and the speedo needle
wobbles a little? Hey, that's not what I think, but obviously a lot of
5.0 guys think that way or vendors wouldn't be selling the things.

The bottom line is that there probably isn't enough of a demand and/or
profit margin for such a device. Otherwise, you can bet your a*s that
some vendor would be telling you that you need one and to buy it NOW!
What the heck, maybe I'll make one and sell it. If I market it right
and tell people it's worth at least 2 tenths and 3 MPH, there'll be a
line out the door for them!!!

Greg Powers
((email redacted))

This read-only message was archived from a public mail list.
Mail From: "Fontana Peter" <(email redacted)>

> With all the problems/expense with the speedo-gear, I wonder
> if it might be a good idea to have a simple external gear setup
> that goes between the speedo and the trans.
> Then one could easily just swap gears in that box to calibrate
> the speedo correctly. This would make it easy to adjust to
> different tire sizes too, not just different rear-end gears.

You know, it really isn't *that* tough to get the tailshaft off the T-5 to
just swap the gear - as I recall we had list member do it while the tranny
was still in the car.

Another point to ponder - these gear swaps are all in the context of a rear
end gear swap - not easy itself. If you're good enough to swap rear gears on
an 8.8 (not just a pumpkin swap like on a 9", then dropping trans xmember
down and pulling the trans tailshaft while your under there shouldn't bee
too bad... ;-)

There are speedo drive reduction gear units out there already, but anything
with moving parts costs at least $50 these days...